drm/amdgpu: add nv common ip block support for van gogh

This patch adds common ip support for van gogh.

Signed-off-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>